This collection of essays comes from the international project "Science and Democracy". It offers an examination of several controversial issues, within and about science, of wide-ranging social relevance. A partial list runs as follows: the role of scientific technology in shaping our life; the influence of corporations on contemporary medicine; grass-roots activism and new technologies; environmental constraints on economical growth; the HIV/AIDS controversy; the Wakefield trial and the MMR vaccine-autism link; the organ transplant ideology and business; the debate on the terrorist attacks in USA of September 11, 2001; the role of whistleblowers in science; etc. - Contributions by J. Barretto Bastos Filho, H. Bauer, M. Brown, M. C. Danhoni Neves, F. Fabbri, P. Ghisellini, S. Lang, A. Liversidge, C. Lor, M. Mamone Capria, R. Maruotti, D. Mastrangelo, S. Maurano, M. Mazzucco, D. Rasnick, S. Siminovic, S. Ulgiati, M. Walker.